Treatment of metals to be drawn, wiredrawn, or rolled



' at 12 Avenue .Bugeaud, Paris,

Patented Aug 4 1925.

PATENT OFFICE.

GASTON DE DUDZEELE, OF PARIS, FRANCE.

TREATMENT OF METALS TO BE DRAWN, WIREDRAWN, 0R ROLLED.

80 Drawing.

To all whom it may concern:

. Be it known that I, GAs'roN'Dn DUDZEELE, a subject of the Kingzof Belgium, residing France, have invented certain new and useful Improvements in the Treatment of Metals to be Drawn, Wiredrawn, or Rolled, of which the following is a specification.

For the purpose of drawing, wire-draw ing or rolling-metals in order to bring them to therequired shape and dimensions, the

metal requires to be annealed, cleaned and eventually coppered between each operation or pass. It 'has however been recognized that all these intermediary operations may be suppressed by previously coating the metals with a thin layer of lead, but it is advisable, in order to obtain good results,

for the lead to be as pure as possible so as to retain all its properties of malleability and it is necessary that the lead should impre nate effectively the metal'to be worked,

so t at during the wo rkingof it, the layer of lead will not separate from it. 1

By electrolytic or chemical means it is possible to obtain a coating of perfectly pure lead, but the adhesive qualities of this coating are not satisfactory, as this pulverulent and crystalline deposit is easily'removed; moreover the electrolytic or chemical process is not economical as it requires an expensive plant andcareful and constant supervision.

Hot dipping, as actually practiced, there- .fore appears, at first sight, Well adapted to replace electrolytic or chemicsi'coating, but up to the present a layer of pure lead could not be deposited by the ordinary method on iron and copper, for example, these metals having no chemical aflinity for lead. It has been proposed, for ensuring a slow but suflicient deposit of lead, to incorporate in the latter metal a sufliciently effective quantity 5 to 10%) of tin or antimony. However tm and antimony harden lead to such an extent that the ordinary coating process I cannot be applied to the mechanical working of metals.

The chief feature of the present invention consists in the possibility of rolling, drawing or wire-drawing metals without any intermediary operations by causing on such metals an efiective impregnation of lead-by means of first amalgamating the metal to be worked and then lead coating it by immersion in molten lead or any of its I alloys.

. Application filed Isebruary 26, 1923. Serial No. 621,472.

' The mercury presents the following advantage: the instantaneous impregnation of the lead. It may be mentioned that a metal treated as described is not simply covered with a more or less thinsheath of lead liable to be removed or Worn off during the drawing or rolling operations, but the lead "impregnates the metal itself, thus prevent ing the drawing or rolling from causing a direct friction of the ,die, ring, or roller on the metal to be Worked; Up to the end of the rolling or drawing operations, the lead exerts its re lating influence. v, The function of the mercury salt is not only to increase the chemical afiinity be tween the metal to be treated and the lead, but further to give to the metal thus treated such qualities as make it possible to draw or roll it several times without altering its qualities of resistance, elongation, etc., this not being the case when working a 'nonamalgamated metal.

The amalgamation may be effected by immersing the metals to be drawn, rolled or otherwlse worked in a solution of a suitable I .mercury salt.

Amongst others a bath composed as follows gives excellent results:

1 gallon of a. dilute solution of hydrochlonc acid at 6 Baum, saturated with am monium chloride, and 1 ounce of mercury chloride.

After remaining a few seconds in this bath. themetallic articles have acquired a grey colour due to the formation of a complex amalgam. They are then w1thdrawn from this bath and dipped directly into pure molten lead. 1

The lead coated articles are allowed to, cool and may'then be drawn, rolled or wiredrawn without the necessity of any intermediary operation such as annealing, cleaning-or coppering afresh between each operat1on or pass.

It is to be understood that by the expresinto its changed finished form.

2. A process for mechanically working metals to change their form, comprising, treating the surface of a metal starting piece to be worked into a difit'erent finished form 5 with a solution of a mercury salt capable of amalgamating the surface, dipping the metal starting piece into pure molten lead, andthen mechanically working the leadcoated metal piece into its different finished 10 form.

3. A process for drawing metals, comprising, amalgamating the metal to be drawn, then coating it with lead, and then mechanically drawing the lead-coated metal.

In testimony whereof I have signed my 1 name to this specification.

. GASTON DE DUDZEELE. Witnesses: T. ARMENGAUD,

I-I. Dnrizvlmuon'r. 

